X 



APPENDIX. 



In a rough way it may therefore be said that the monthly heat is felt to a height of 

 two miles, and the daily to a height of one-filth of a mile. 



The chief advantages of a Barometric register, are the means it affords of finding 

 the respective altitude of places : to this point I have paid all the attention in my 

 power, particularly to the determination of the height of Benares above Calcutta ; for 

 which the Register published (but again discontinued) by the Surveyor General's 

 Office afforded me the principal data. 



The heights of the Barometers at the same hours at the two places, corrected to 

 the same index, and both reduced to the temperature of 32° Farh. give the follow- 

 ing differences j inch. 



April, 1822, 0.283 



June, 0.261 



Ditto, noon, 0.253 



August, 0.263 



December, 0.240 



January, 1823, noon, 0.214 Mean of the whole. 



Ditto, 5 p. m 0.214 indies. 



February, noon, . . 0.265 0.1.501 



5 p.m. . 0.217 



April, noon, 0.261 or Calcutta Barometer, 29.9000 



May, 0.250 Benares, 29.6499 



June, 0.289 



July, 0.239 



August, 0.268 



September, ........ 0.250 



Captain Hodgson has omitted to give the temperature of the external air in his 

 tables, but supposing the mean to be 80°, the Barometrical altitude of Benares above 

 Chowringhee is 246.75 feet. I believe Capt. H. estimated it at 500 feet. 



A few comparisons of a similar nature made with Captain Herbert, give the height 

 of Cawnpoor 133.3 feet above Benares.* 



* Since writing the above, some further communications from Captain Herbert have enabled me to calculate the heights of 



three other places above Benares ; namely, 



Futtigurh Cantonments, from six comparisons, 249.0 feet. 



Bumouree, foot of the hills, from six comparisons, 1407.4 feet. 



Almorah, from three observations in January, 1824, ...... ...... 4887.0) 



from five ditto, in February, . , ... ...... 4810.5 J meaa * 83Sl ' 5 feet ' 



